Congress last week passed a bill penalizing Russian officials accused of rights violations. Russian officials have bristled at the bill, which they interpret as U.S. intervention in Moscow's domestic affairs, and they have vowed to retaliate.

Putin described the U.S. bill as "a politicized and unfriendly act" and lauded the State Duma's planned response, Interfax reported.

"I can't understand why one has to sacrifice Russian-U.S. relations in favor of reaping a political dividend," he said.

The U.S. bill is named for Russian lawyer Sergei Magnitsky, who was arrested by police officials he accused of a $230 million tax fraud. He was repeatedly denied medical treatment, and in 2009, he died in jail.

Rights groups accused the Kremlin of failing to prosecute those responsible. Moreover, the officials that Magnitsky accused of fraud were promoted.

Putin said that the investigation into the lawyer's death is ongoing and that "it's not clear yet who's right or wrong there."

On Monday, pro-Kremlin lawmakers submitted a bill to the State Duma with measures against U.S. citizens "who are rudely violating human rights."

In a move widely seen as punishment for the U.S. bill, Russia will also start requiring all shipments of U.S. beef and pork to be tested and proved free of an animal feed additive called ractopamine. The measure effectively amounts to a ban because the U.S. considers ractopamine safe and does not test for it.

On Thursday, Putin said he wondered why Americans were paying so much attention to a Russian jail death, and he suggested that deaths behind bars are frequent in the U.S.